1. Field of the Invention
This invention relates to mount baseplates for mounting load beams to actuator arms in disk drive suspensions, and more particularly to an improved mount baseplate having reduced mass while maintaining a thickness desirable for mechanical properties, the mass reduction being made at performance-noncritical areas of the baseplate.
2. Description of the Related Art
Typically a disk drive suspension comprises a steel load beam having a base section that is weld-attached to a mount comprising a baseplate. The baseplate is attached to the drive actuator arm such as by swaging the baseplate boss into engagement with an aperture in the arm. Typical thicknesses of the 0.200 by 0.200 inch planar portion of the, baseplates are in the range of 0.004 inch at a minimum to 0.008 inch that is currently preferred. The lower thicknesses may not provide adequate mechanical properties. Since the area is reasonably unchangeable, reducing the baseplate mass has centered on reduced thickness in the planar portion, but thicknesses are presently at the minimum.
It is an object of the invention, therefore, to provide for use in disk drive suspensions an improved baseplate that has reduced mass but that maintains the desired thickness for mechanical properties. It is a further object to contour the common baseplate in areas not critical to performance to reduce mass without undue loss in mechanical properties. Yet another object is to provide a novel shape in a baseplate that accommodates all mechanical requirements, such as maintaining the base plate edge at the load beam spring section, keeping a minimum thickness or greater, and providing distributed welding sites, while having a reduced mass.
These and other objects of the invention to become apparent hereinafter are realized in a low mass baseplate for attaching a suspension load beam having a rigid section, a spring section and a base section by its the base section to an actuator arm, the baseplate comprising a planar portion attachable to the load beam base and integrally formed therewith a boss portion attachable to an actuator arm, the planar portion having a front edge and a rear edge and left and right lateral edges therebetween, the boss portion comprising a cylinder spaced inwardly from the planar portion edges and having a given outside diameter, the planar portion having a front edge recess in mass reducing relation, the recess defining with the left and right edges respectively left and right legs, the legs having a lateral extent greater than the boss portion outside diameter, whereby adjacent baseplates do not become entangled with each other in tumble deburring operations.
In this and like embodiments, typically, the left and right leg portions define left and right front edges, the edges being adjacent left and right spring areas respectively of the load beam spring section, the baseplate rear edge and the left and right lateral edges are radiused at their intersection in mass reducing relation, and the baseplate rear edge comprises a smooth curve commencing at the center of the rear edge and terminating on the left and right lateral edges of the planar portion at left and right points opposed across the boss.
Typically, the planar portion and the load beam base section are welded to each other at laterally and longitudinally distributed points between the most rearward part of the boss and the planar portion front edge.
Preferably, the recess is V-shaped with its open mouth adjacent the load beam spring section, or the recess has the shape of the interior opening in a U with its open mouth adjacent to the load beam spring section.
In a further embodiment, the invention provides a low mass baseplate for attaching a suspension load beam having a rigid section, a spring section and a base section by its the base section to an actuator arm, the baseplate comprising a metal planar portion weld-attachable to the load beam base and integrally formed therewith a cylindrical boss portion attachable to an actuator arm, the planar portion having a front edge and a rear edge and left and right lateral edges therebetween, the boss portion comprising a cylinder spaced inwardly from the planar portion edges and having a given outside diameter, the planar portion having a distal front edge recess coaxial with the boss portion and spaced therefrom, the recess being devoid of metal in mass reducing relation, the recess defining with the left and right edges respectively left and right legs, the legs having a lateral extent greater than the boss portion outside diameter, whereby juxtaposed baseplates do not become entangled with each other in tumble deburring operations.
In this and like embodiments, typically, the low mass baseplate planar portion recess has an extent along its lateral axis greater than its extent normal to the lateral axis, the recess terminates inwardly in a pointed or radiused terminal, the left and right leg portions define left and right front edges, the edges being adjacent left and right spring section areas respectively of the load beam spring section, the baseplate rear edge and the left and right lateral edges are radiused at their intersection in mass reducing relation, and the baseplate rear edge comprises a smooth curve commencing at the center of the rear edge and terminating on the left and right lateral edges of the planar portion at left and right points opposed across the boss.
The invention further provides in combination, the low mass baseplate described and a load beam having a base section, the baseplate planar portion being weld-attached to the load beam base section at laterally and longitudinally distributed points between the most rearward part of the boss and the planar portion front edge.